The central concern of Adi Shankaracharya's writings is the liberating knowledge of the true identity of jivatman (individual self) as Ātman-Brahman.
According to him, the one unchanging entity (Brahman) alone is real, while changing entities do not have absolute existence. Shankara's primary objective was to explain how moksha isattained in this life by recognizing the true identity of jivatman as Atman-Brahman, as mediated by the Mahāvākyas, especially Tat Tvam Asi, "That you are."
Correct knowledge of jivatman and Atman-Brahman is the attainment of Brahman, immortality, and leads to moksha — liberation from suffering and samsara, the cycle of rebirth. This is stated by Shankara as follows:
I am other than name, form and action.
My nature is ever free!
I am Self, the supreme unconditioned Brahman.
I am pure Awareness, always non-dual.
— Adi Shankaracharya, Upadesasahasri 11.7
Here are some quotations from his writings about Knowing one's Self:
"The world, like a dream full of attachments and
aversions seems real
until the awakening."
ॐ
"Each
thing tends to move towards its own nature.
I always desire happiness which is my true nature.
My nature is never a burden to me. Happiness is
never a burden to me, whilst sorrow is."
ॐ
"Even after the Truth has been realised, there
remains that strong,obstinate impression that one
is still an ego - the agent and experiencer. This
has to be carefully removed by living in a state of
constant identification with the supreme non-dual
Self. Full Awakening is the eventual ceasing of all
the mental impressions of
being an ego."
ॐ
"As gold purified in a furnace loses its impurities
and achieves its own true nature, the mind gets rid
of the impurities of the attributes of delusion,
attachment and purity through meditation and
attains
Reality."
ॐ
"Thus one should know oneself to be of the nature
of Existence-Consciousness-Bliss[Sat-Chit-
Ananda]."
ॐ
"The witness of the three states of consciousness
[waking, dream and deep sleep] and of the nature
of Existence-Consciousness-Bliss is the
Self"
ॐ
"Who but the Atman is capable of removing the
bonds of ignorance, passion and self-interested
action?"
ॐ
